In the process and as a test case of the module/file-handling, separate
Array.p.forEach into its own Torque file.

Bug: v8:7793
Change-Id: If45103a9df3bf8fade34e7bcf7c7c9c060e25966
Reviewed-on: https://chromium-review.googlesource.com/1097755Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Daniel Clifford <danno@chromium.org>
Cr-Commit-Position: refs/heads/master@{#53703}